Metal coil



Jan. 18, 1938. Q s, HENDERSON 2,105,734

METAL COIL Filed Nov. 11, 1935 2 Sheets-Sheet l J2 J3 ZZZ 1 11 12 Jan. 18, 1938.

Filed Nov. 11, 1935 C. S. HENDERSON METAL COIL 2 Sheets-Sheet 2 Patented Jan. 18, 1938 Clarence S. Henderson, Batavia, 111., assignor to Acme Steel Company, Chicago, 11., a corporation of Illinois Application November 11, 1935, Serial No. 49,246

1 Claim.

This invention relates to improvements in coils of steel strapping and the like and to methods of forming the same according to which these coils are formed in an improved manner so that they retain their original shapes and conditions during the process of shipment and. until they have been entirely consumed by the user. It has heretofore been the usual practice to wind flexible steel strapping in the form of coils in such a manner that there are several spiral layers of strapping side by side. After being wound, the ends of these coils have been secured and they have been removed from the winding drums and shipped in that condition to the user who, during the process of use, has placed the coil on a rotatable drum and unwound the metal from the outer side thereof. These coils have ordinarily been of rectangular cross-section with the edges of the metal strips at opposite sides of the coil lying in parallel planes and with the inner and outer layers of the coil lying in concentric circles. However, it has been found that during the process of loading and shipment, these coils often receive severe shocks and jolts which sometimes cause all of the layers or convolutions oi the metal at one side of the coil to be deflected or bowed inwardly, in conjunction, usually, with a lateral spreading of the metal in this part of the coil. This bulging and spread of the metal has interfered with the unwinding of the coil in use and it has usually been found impossible to restore the distorted part of the coil to its original shape after it has once been deflected therefrom, with the result that many coils have to be scrapped or returned to the factory for rewinding.

The present invention involves the discovery that a metal coil of this character may be retained in its original shape under all ordinary conditions by winding the strip of metal initially upon a light flexible core or drum, formed preferably of thin wood veneer, which is allowed to remain in the coil during its packing and shipment and during the subsequent use of the metal strapping by the consumer. When wound in this manner, the coil retains its original circular shape under all ordinary conditions and even when subjected to the shocks and blows which have heretofore been sufficient to effect the distortion complained of, and if, when an unusually severe blow imparted to the coil of the present invention results in its distortion, it is found that with the flexible core or drum on the inside of the coil, an outward pressure will restore this portion of the coil to its original arcuate shape. The principal object of the invention, therefore, is to provide an improved coil comprising a light flexible core or drum having wound thereon a plurality of concentric convolutions of metal strapping or the like. Another object is to provide a core for metal coils comprising a plurality oflayers of thin flexible veneer secured together. Still another object is to provide an improved method of forming a coil comprising the steps of forming a thin flexible core or drum made up of a plurality of laminations of thin veneer, then attaching one end of the metal strapping to the drum and winding the strapping thereon to form a plurality of concentric and parallel layers which make up a body of metal of substantially rectangular cross-section, and finally securing the core and the layers of metal together to prevent their lateral or relative displacement during shipment. Other objects relate to various features of construction and arrangement and to details of the improved method which will appear more fully hereinafter.

The nature of the invention will be understood from the following specification taken with the accompanying drawings, in which one embodiment of the improved coil construction and one example of the improved method are illustrated. In the drawings,

Fig. 1 shows a top plan view of the improved coil of the present invention;

Fig. 2 shows a side elevation of the coil illustrated in Fig. 1;

Fig. 3 is a perspective view of the improved flexible core or drum upon which the metal is wound;

Fig. 4 is a perspective view of the layers or 3 laminations of veneer which are employed in the construction of the core shown in Fig. 3;

Fig. 5 shows an enlarged section taken through a portion of the coil transversely to the axis thereof, showing the means for attaching the metal to the core and the means for preventing relative separation of the core and the convolutions of metal; and

Fig. 6 is a transverse section taken on the line 6-6 of Fig. 5.

As illustrated in the drawings, the improved coil of the present invention comprises a circular core or drum l0 formed preferably of two or more layers of wood veneer or the like, and having wound thereon a single length of steel strapping H which is relatively narrow as compared with the width of the core It and which is wound with a number of concentric and laterally parallel convolutions so that the resulting body of metal is of substantially rectangular cross-section and.

is made up of a number of circular layers H each formed as a spiral coil. When the winding of the coil has been completed, the core and the metal are secured against relative displacement at a plurality of points by winding strips of cardboard 12 or the like laterally around the built-up coil and then winding around each of these protective sheets I2 a flexible binder I3 which, in this instance, is shown as being in the form of a round wire having its ends twisted together as shown at Et after the wire has been drawn taut around the coil.

The core It is preferably made up of a number of layers iO Ni and IB of comparatively thin material, such as wood veneer, which has considerable flexibility but which is adapted to retain the circular shape of the completed core when the layers of laminations have been secured together. The two long layers Mi and lt are wound one upon the other, as shown in Fig. 3, with the diagonally cut ends of each strip in proximity to each other but with the joint at the end of one I strip arranged in staggered relation to the joint at the end of the other strip. The joint in the outer strip is protected and reenforced by the insertion between the layers Mi and iii", at this point, of the short layer ID. All of the layers are secured together adjacent the joints by diagonal rows of staples M which are arranged on opposite sides of each joint. Other staples 15 may be passed through the layers of the core at other places around its circumference and, if desired, the layers may be glued or otherwise secured together. At one point around the circumference of the core or drum, preferably opposite the intermediate layer 10, the two layers it and I0 are provided with a central aperture Hi of rectangular form which is of substantially the same width as the metal strip l l to be wound on the core.

In the process of forming the coil, after the core H? has been completed in the form shown in Fig. 3, one end li of the metal strapping H is inserted through the aperture lt from the outer side of the core and is reversely bent as shown in Fig. 5. With the core Ii) placed upon the usual rotatable winding drum, the winding of the long strip of metal then continues until all of the concentric and laterally parallel layers of metal have been completed to form a. body of metal of the desired radial thickness and of substantially the same width as the core it. One of the protective sheets 12 of fibreboard or the like is then placed around the completed coil adjacent the outer end of the metal strip and this outer end is then reversely bent as shown at M in Fig. 5. One of the wires I3 is then drawn taut around the protective sheet I2 and its ends are twisted together, after which the outer extremity of the metal strip H is bent in the opposite direction over the wire i3, as shown at li When this has been done, other protective sheets :2 and binding wires it are applied to the coil at other points around its periphery. It is usually desirable to employ at least three or four of the protective sheets i2 and a corresponding number of binders 53. The coil is then completed, ready for shipment, and it has been discovered that if during loading or transit the coil be dropped, for example, so that a heavy blow is imparted to one side thereof with the result that a portion of the coil is bowed inwardly as shown by dotted lines at l5 in Fig. 2, this inward bulge may be eliminated by an outward pressure on the inner side thereof with the result that both the flexible core ill and the surrounding body of metal are restored to their original shapes. If a similar bulge or distortion had occurred in a body of metal wound in a coil formed according to the old practice, the distortion would have been permanent and could not have been eliminated.

It will be understood that the invention may be constructed in various embodiments, not herein illustrated, without departing from the scope CLARENCE S. HENDERSON. 

